Teak is definitely the best choice. There are some other less expensive woods if you can find them. Canarywood is one. Locust is very rot resistant. I would not use oak or mahogany. They are both subject to rot rather quickly if not completely sealed all the time which, as we know, is really not feasible. The characteristics of hardness, workability, and rot-resistance are not present in many woods.

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Alberg 35: With a philosophical flourish Cato throws himself upon his sword; I quietly take to the ship.